[
https://issues.apache.org/jira/browse/IOTDB-452?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17029806#comment-17029806
]
Xiangdong Huang commented on IOTDB-452:
---------------------------------------
+1 .
It is a basic optimization for the query process.
Even if there is no group by clause, the aggregations should also only depend
on one Reader for one path.
e.g., select avg(s1), count(s1), first(s1) from root.sg.d1.
> Do all aggregations of one series at one pass in GroupBy
> --------------------------------------------------------
>
> Key: IOTDB-452
> URL: https://issues.apache.org/jira/browse/IOTDB-452
> Project: Apache IoTDB
> Issue Type: Improvement
> Reporter: Jialin Qiao
> Priority: Minor
>
> For example
>
> select avg(s1), count(s1), first(s1) from root.sg.d1 group by ([100,199],10ms)
>
> We could just construct one aggregate reader and get three aggregation
> results at one pass.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
